<?php
class TimeUtil{
	public static function mysql2php(){

	}

	public static function php2mysql(){

	}

	public static function yesterday(){
		return strtotime(date('Y-m-d',strtotime("-1 day")) . ' 00:00:00');
	}

	public static function today(){
		return strtotime(date('Y-m-d') . ' 00:00:00');
	}

	public static function now(){
		return strtotime("now");
	}
}